The invention relates to a support structure for vehicle airbag.
Such airbags are known from the series-production of motor vehicles, especially of passenger vehicles. After having been used initially in particular to protect the driver or the passenger, for some years they have also been used widely as lateral airbags in the region of the side doors, as head airbags in the region of the lateral glazing or at another location within the motor vehicle.
A particular ambition with the development of airbags is thereby amongst others to arrange the airbag in its restraint position as large and as optimal as possible, so that it has a beneficial restraint effect. Additionally, it shall be achieved by a beneficial OoP behavior (out of position) of the airbag that a vehicle occupant is held back even with a poor or unusual sitting posture in the case of a collision, without experiencing unnecessary loads by the airbag itself. A deployment behavior of the airbag to the restraint position shall be achieved by a beneficial LRD behavior (low risk development), by means of which the seat occupant is affected in a correspondingly low manner.
It is thus an object of the present invention to create a support structure for an airbag of the type mentioned at the outset, by means of which the protective properties of the airbag can be improved further.
This and other objects and advantages are achieved by the support structure according to the invention, which can be moved or enlarged from a storage position to a restraint position by a gas flow, and which comprises a plurality of hollow bodies connected to each other that form a channel system, with means being provided for the targeted influencing of the gas flow are provided within the channel system. In other words, a framework- or frame-like support structure is for example presently provided in the restraint position, which consists of a plurality of hollow bodies—for example tube bodies. The latter are connected with to each other in a gas-guiding channel system. To improve the protective function of the airbag in a targeted manner, means are provided within the channel system for the targeted influencing of the gas flow, by means of which for example the filling time, the filling sequence, the deployment behavior, the OoP behavior and the LRD behavior of the support structure or of the airbag can be influenced in a targeted manner. It can be seen that these measures all serve for the improved protective function of the airbag.
By the targeted influencing of the gas flow, it can thereby be achieved for example that individual partial regions of the support structure are supplied in a temporally different manner or with different pressure. It is thereby possible, for example, to achieve targeted movement or deployment shapes of the support structure or of the airbag. By the targeted influencing of the gas flow by effecting a different pressure, the restraining effect of the support structure can also be influenced.
The support structure itself is preferably surrounded by a casing or the like, so that ambient air enclosed within the support structure can be consulted for the restraining effect. This takes place, for example, in that, during the impact of the seat occupant on the airbag in the restraint position, the internal pressure is built up within the support structure provided with the covering, whereby the restraint results. It is thereby of particular importance that the pressure builds up in the volume enclosed within the support structure as efficiently as possible.
In a further arrangement of the invention, it has further been shown to be advantageous if at least one guide element is arranged within the channel system, by means of which the gas flow shall be guided. It is thus possible in a simple manner during the deployment or moving of the airbag to the restraint position, to carry out for example a division of the gas flow between individual hollow bodies or partial regions of the channel system. Depending on how far the guide surface projects into a corresponding hollow body, a volume flow can thus be determined, which shall further flow in one direction or the other. Altogether, a simple possibility for the targeted influencing of the gas flow is thus created.
In a further development of the invention, the at least one guide element is provided in the region of a connection of two hollow bodies of the channel system in a preferred manner, so as to thus carry out in an indirect manner a division of two partial gas flows between two partial gas flows, which are to be guided to the respective hollow bodies.
In a further advantageous embodiment, it is provided that at least one closure element is arranged within the channel system, for closing an associated hollow body. A flow in a corresponding hollow body or of a partial region of the support structure can thus be avoided or stopped in a targeted manner, wherein a deflection of the gas flow to another partial region of the support structure can be realized by this closure. It is obvious that the sequence or the deployment behavior of the support structure or of the airbag can again be influenced hereby in a targeted manner. A stopping or deflection of the gas flow for influencing the filling sequence is hereby possible.
In a further arrangement of the invention, it is provided that at least one cross sectional change of an associated hollow body is provided within the channel system. This cross sectional change can thereby be provided in an extremely localized or partial manner, or can also take place over longer path progressions of the hollow body. By this measure, the flow resistance within the respective hollow body or the respective partial region of the support structure can be adapted correspondingly to the appropriate distribution. In other words, the flow behavior of the gas flow can be influenced correspondingly by the targeted cross sectional change, so as to for example generate a corresponding filing sequence or a corresponding deployment behavior. The targeted cross sectional change of the associated hollow body can also be used for influencing the flow and/or pressure ratios in the hollow bodies, in order to for example cause or avoid constrictions in a targeted manner, which can be caused by the Bernoulli effect.
It has further been shown to be advantageous if at least one valve is arranged within the channel system as a means for influencing the gas flow, by means of which valve the gas flow can be adjusted. A membrane functioning in the same manner would naturally also be conceivable instead of a valve. By means of such a valve it is thus possible to adjust a different pressure in individual hollow body sections or partial regions of the channel system. It is thereby for example possible to use part of the gas filling or of the gas flow for filling and heating the restraint volume, while another part remains in the support structure or in the channel system, so as to achieve a restraint effect or re-establishment of the restraint volume. With a labyrinth and/or obstacle construction which can be generated thereby, the deployment sequence and speed can be controlled correspondingly. In a further arrangement of the invention, the at least one valve can thereby also be formed as a check valve.
In a further development of the invention, it is additionally provided that at least one closure element is arranged within the channel system, by means of which an associated hollow body can be closed. It would thereby be particularly conceivable to use a flap or the like instead of a valve, by means of which a gas flow can flow through the hollow body in one direction, but not in the other direction.
It has finally been shown to be advantageous in a further embodiment of the invention if at least one hollow body of the channel system has a nominal bending location. The OoP behavior and the LRD behavior can also be influenced hereby in a beneficial manner.
This is especially characterized in that a plurality of hollow bodies are provided, which are connected to each other, that form a channel system, wherein a plurality of the hollow bodies forms an outer structure of the support structure, and wherein at least one hollow body is provided, by means of which hollow bodies of the outer structure are connected to each other. Accordingly, at least one hollow body is provided, which not only proceeds at the outer surface or surface of the support structure, but also through its restraint volume. Hereby, corresponding partial regions of the outer structure of the support structure can be connected to each other in a suitable manner, so as to optimize the deployment and possibly also the support behavior of the support structure or of the airbag. Thus, a shortcut can be created by means of the hollow body projecting through the restraint volume so as to optimize the deployment and the support behavior of the support structure or of the airbag. Furthermore, the at least one hollow body, which passes through the restraint volume, can be used for the supporting or stiffening of the support structure or of the airbag.
It has finally been shown to be advantageous if a gas generator which generates the gas flow is connected to a plurality of hollow bodies, so as to achieve a fast distribution of the medium within the channel system.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.